Field
The described technology generally relates to rechargeable lithium batteries.
Description of the Related Technology
Lithium rechargeable batteries have recently drawn attention as a power source for small portable electronic devices, and use an organic electrolyte. A lithium battery may have twice or more discharge voltage than a conventional battery using an alkaline aqueous solution, and accordingly have high energy density.
As for positive active materials of a rechargeable lithium battery, a lithium-transition metal oxide having a structure being capable of intercalating lithium ions, such as LiCoO2, LiMn2O4, LiNi1−xCoxO2 (0<x<1), and the like has generally been used. As for negative active materials, various carbon-based materials such as artificial graphite, natural graphite, and hard carbon that may intercalate and deintercalate have generally been used.
An electrode may be formed by coating slurry in which an active material, a binder, and a solvent are mixed and dispersed on a current collector and drying the same. Herein, when the slurry is coated to be greater than or equal to a predetermined level, i.e., thickness, the coating layer may have weak adherence to the current collector and thus, cause a crack on an electrode. In order to improve this problem, more binder may be included, which may deteriorate impregnation of the electrode. The deteriorated impregnation of the electrode may subsequently deteriorate battery performance such as cycle-life and the like.